Metal-casting machine.



J. J. MCGUIRE.

METAL CASTING MACHINE.

APPLICATION FILED JAN. 22, 1914.

1, 1 1 6,720. Patented Nov. 10, 1914.

WITNESSE 2 A ORNEYS JAMES J. MOGUIRE. OF NEWARK, NEW JERSEY.

METAL-CAS TING MACHINE.

Specification of Letters Patent.

Application filed January 22, 1914. Serial No. 813,684.

To all whom it may concern Be it known that I, JAMES J. MCGUIRE, a citizen of the United States, and a resident of Newark, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Metal-Casting Apparatus, of which the following is a specification.

This invention relates to an apparatus for casting metal and is adapted for use where the metal is. flowed in its molten form ,into acavity in the investment material of the mold, and is particularly adapted for the purpose of making inlays for dental purposes.

The invention is designed to provide an apparatus of this type, which is complete in itself, embodying a vacuum chamber, a suction mechanism, a suitable indicator and flask support, all these being conveniently arranged, and being disposed to provide for economy in manufacture, and also arranged to facilitate the use thereof.

The apparatus further consists in;so constructing the apparatus to use a mlmmum number of parts, and to construct the flask support so that it also acts to draw and hold together the parts of the vacuum chamber, whereby, if necessary, access can be easily had to said chamber.

A further object of the invention is to so aflix the pump so that it is in a convenient position with its check-valve projecting within the vacuum chamber, the valve being releasable after the removal of the pump.

The invention is illustrated in the accompanying drawing, in which- Figure 1 is a side view broken away in places to show the interior construction of the vacuum chamber, the pump and the flask. Fig. 2 is a top view of the apparatus illustrated in Fig. 1.

I am aware that machines have been constructed for carrying out the same operations which are carried out by this machine,

but they have the disadvantage of having their parts separated to a considerable extent, or they are not easily assembled or taken-apart, and thus employing a vacuum chamber in conjunction 'with the pump, usually take up a great deal of room In my construction the vacuum chamber 10 is formed of a side wall 11 of any desired shape, but shown in the drawin as cylindrical. At the bottom thereof is a base 12 with an annular shoulder 13 against which the wall 11 rests, the end of the wall abutting against the bottom plate. The bottom plate projects beyond the edges of the wall and has suitable holes 14 by means of which it receives screws or the like to fasten the apparatus to a support if desired. It will be understood, however, that other means of fastening the apparatus can be used. The top plate 15 has an annular shoulder 16 near its edge, the side wall 11 abutting against the shoulder 16. A stem 17 is arranged in the vacuum chamber, preferably in the center thereof, and has a screw-threaded end 18 which screws into the screw-threaded opening 19 of the base plate 12, the stem extending beyond the top plate 15, and having a screw-threaded portion 20 screwing into the screw-threaded perforation 21in the top plate and extending sufficiently above the top plate to provide for the valve casing 22 being screwed thereon. It will be seen that the vacuum chamber is drawn together and held with its 'parts'in close and tight contact by screw ing the top and bottom plates on the portions 18 and 20 of the stem 17, the whole being locked together by the portion of the valve casing 22 which screws on the end 23 of the stem 17, thereby acting as a lock-nut. The valve casing 23 can be provided with any desired form of valve mechanism, the

usual form being an ordinary cock with a handle 24 for opening and closing it. On the top of the valve casing 22 is a pipe 25 which has arranged on the top thereof a flask support 26. The flask support can be removable so that different sizes can be placed on the pipe 25, the flask support being preferably held in place by the screwthreaded portions 27 which screw together and hold the pipe 25 and the flask support 26 in their proper relation, the flask support and the pipe both being perforated 1n line so that the passage of air is free from one to the other. Any suitable flask 28, as now used by dentists, can be employed, the flask containing a suitable investment material 29 into which the cavity 30 is formed, into which cavity the molten material is to be molded by casting. The gate or sprue 31 is formed as is usually done in this type of mold, and the metal when placed in the recess 32 is ready for being deposited in the cavity 30. The material is sometimes poured on the mold, and other times it is placed Patented Nov. 1%, 1914.

thereon in its unmolten shape and then subjected to the action of a blow-torch or the like.

My apparatus has been designed particularly with a view to adapting it for use with a blow-torch so that the flame can be directed thereon from any side without the flame operating on other parts of the apparatus to mar or burn them, or to interfere with their operation. The gage 33 is placed at one sideof the vacuum chamber with its indicating surface 34 facedupward so that it is normally in view of the operator of the pump, but is removed from the vicinity of the flask so that it is not subjected to, and therefore is not liable to injury or cracking from, the flamehof the torch.

Arranged on the side of the vacuum chamber, and preferably on the side opposite the gage or indicator 33 is a suction pump 35 arranged parallel withthe vacuum chamber and with its upper endsupported in a collar 36 which is attached to and preferably integral with the top plate 15. The

pump cylinder has at the bottom thereof a collar 37, having a nut 38 at one side thereof, the nut screwing over a screw-threaded extension 39 of the check-valve casing 40, the check-valve casing having a screwthreaded portion 39 screwed into a screwspring 48, which abuts on the collar 47 and on the end of the check-valve casing 40. The pump 35. has a suitable piston rod 49, on which is arranged a piston 50, the piston being of the usual type in pumps of this kind with a leather or other suitable ring fitting the inside of the pump, and constructed to allow air to pass by it when it descends, being locked against the passage of air when it ascends, the air being ejected through a suitable opening at the topfas at 51, the projecting end of the piston rod 49 having a handle thereon.

When the apparatus is to be used the pumpis operated to withdraw the air fromthe vacuum chamber until a suitable amount of vacuum is in the chamber, as indicated on the gage 33. While the air is being withdrawn from the vacuum chamber the valve handle 24 is turned to shut the valve, and there is no passage of air through the pipe 25. When a suitable amount of pressure is available for use on the top of the pipe 25, the pump handle 52 is placed at its lowest position so that it is out of the way from a blast from a blow-torch or heating mechanism.that might be directed on the flask, and the flask is put in place, the flask containing the usual investment material with a cavity that is to be filled with the molten material. When the metal is melted to a proper consistency, the valve handle 24 is turned to open the valve 53, and a pressure is induced against the top surface of the flask, since the air is induced to pass through and against the investment ma terial 29, and through the pipe 25, through the pipe 52, and also through the passage 54 which is formed part way through the stem 17, and emerging as at 55 into the vacuum chamber 10.

This apparatus is compact and is a stiff and solid construction, the parts being so disposed so that they cooperate to form a unitary device which is complete in itself,

and in which the operating parts and the indicator are arranged far enough away from the flask to be removed from the liability of injury through the use of a blast against the flask, andat the same time are conveniently arranged for use, since the person operating the pump, inanticipation of the use of the torch, is in a position to observe the indicator to see what pressure is being available for use on the mold.

Having thus described my invention, what I claim is:

1. A metal casting apparatus comprising a vacuum chamber, a pump vertically disposed at one side of the chamber, a gage projectmg from the side of the chamber,

a valved pipe projecting vertically from the chamber above the other-elements, and a flask support at the topv of the pipe.

2. A metal casting apparatus comprising a vacuum chamber that is vertically disposed, a vertically disposed pump secured to the side of the chamber, a check-valve between the chamber and the pump at the bottom thereof, astem in thechamber and secured to the top and bottom thereof, and projecting from the top, a valve on the top of the stem, the stem having a passage leading from its end and projecting from the side within the casing, a pipe on the valve and having its top end above the pump, and a flask support on the top of the pipe.

3. A metal castingapparatus consisting of a vertically disposed vacuum chamber consisting of aside wall, a. bottom plate and a top plate, a stem secured topthe bottom plate and top plate andconnecting them,

from the chamber and having a passage from its projecting end. to the inside of the the stem having its upper end projecting chamber, and v a valved pipe on the top of Y of a vertically disposed vacuum chamber,

the vacuum chamber consisting of a cylindrical sidewall, a bottom plate and a top plate, the bottom and top plates being provided with annular shoulders against which the side wall rests, a stem projecting from the top of the chamber and having means co-acting with the top and bottom plates to draw them toward each other when the stem is rotated, 21. valve screwing on the end of the projectin portion of the stem and acting to lock t e stem against rotation, a pipe projecting from the valve, and a flask support on the top of the pipe.

5. A metal casting apparatus consisting "co-acting with the top and bottom plates to draw them toward each other when the stem is rotated, a valve screwing on the end of the projecting portion of the stem and acting to lock the stem against rotation,

pump and screwing on to the screw-threaded portion of the check-valve.

6. A metal casting apparatus compris mg a vacuum chamber consisting of a vertically disposed side wall, a top plate and a bottom plate, the plates having shoulders against which the side wall is adapted to rest, screw-threaded perforations in the plates, a stem having screw-threaded portions to engage the screw-threaded opening of the plates, whereby the plates are drawn tightly toward each other and against the side wall, the stem having a screw-threaded portion at the top projecting above the top plate, a'valve casing screwing on to the projecting portion of the stem and acting as a lock-nut thereon, the stem having a passage extending from its top end and opening-into the chamber, a pipe projecting up from the valve casing, a

flask support on the top of the pipe, a pump mounted on the side of the chamber, and a check-valve between the chamber and the pump.

In testimony that I claim the foregoing, I have hereto set my hand, this 17th day of January, 1914.

JAMES J; McGUIRE.

Witnesses:

WM. H. CAMFIELD,

M. A. JOHNSON. 

